brakes CHEVROLET DYNASTY 1993 Workshop Manual

(9) Remove the inboard brake shoe assembly by
sliding it out along the bottom adapter abutment un-
til brake shoe assembly loosens from anti-rattle clip
(Fig. 7). (10) Remove the anti-rattle clip from the top
adapter abutment (Fig. 8).BRAKE SHOE INSTALLATION
(1) Thoroughly clean and lubricate both adapter
abutments with a liberal amount of Mopar tMulti-
purpose Lubricant, or equivalent. (2) Install the anti-rattle clip on the upper abut-
ment of the caliper mounting adapter (Fig. 8). (3) Install the new inboard brake shoe assembly on
the adapter by sliding it along the adapter abut-
ments. Be careful not to get any grease from the
adapter abutment on the surface of the brake lining
Fig. 4 Storing Caliper
Fig. 5 Removing and Installing Outboard Shoe Assembly
Fig. 6 Removing or Installing Braking Disc
Fig. 7 Removing or Installing Inboard ShoeAssembly
5 - 36 BRAKES Ä

material, (Fig. 7). Be sure inboard brake shoe assem-
bly is correctly positioned against anti-rattle clip
(Fig. 6). (4) Reinstall the Braking Disk on the hub, by in-
stalling it over the wheel studs until it is seated
against the face of the hub (Fig. 6). (5) Slide the new outboard brake shoe assembly on
the adapter abutment, (Fig. 5). (6) Carefully lower caliper over the braking disk and
brake shoe assemblies (Fig. 3). Make sure that the
caliper guide pin bolt, bushings and sleeves are clear of
the adapter. (7) Install the caliper guide pin bolts and tighten to
34 to 37 N Im (25 to 35 ft. lbs.). Extreme caution
should be taken not to cross the threads of the
caliper guide pin bolts. (8) Install the wheel and tire assembly. Tighten the
wheel mounting stud nuts in proper sequence (Fig. 9)
until all nuts are torqued to half specification. This is
important. Then repeat the tightening sequence to the
full specified torque of 129 N Im (95 ft. lbs.).
(9) Remove jackstands or lower hoist. Before mov-
ing vehicle, pump the brake pedal several times
to insure the vehicle has a firm brake pedal to
adequately stop vehicle. .
(10) Road test the vehicle and make several stops to
wear off any foreign material on the brake linings and
to seat the brake shoe linings.
Fig. 8 Remove Or Replace Anti-Rattle Clip
Fig. 9 Tightening Wheel Nuts
Ä BRAKES 5 - 37

KELSEY HAYES DOUBLE PIN NON-FAMILY CALIPER INDEX
page page
Assembling Disc Brake Caliper .............. 42
Cleaning and Inspection of Brake Caliper ...... 41 Disc Brake Caliper Disassembly
............. 40
Service Procedures ....................... 38
SERVICE PROCEDURES
BRAKE SHOES REMOVE
(1) Raise the vehicle on jackstands or centered on
a hoist. (2) Remove the front wheel and tire assemblies
from the vehicle. (3) Remove the brake caliper assembly to steering
knuckle attaching guide pin bolts (Fig. 1) (4) Pull lower end of brake caliper out from the
machined abutment on the steering knuckle (Fig. 2).
Then roll caliper out and away from braking disc
(Fig. 2). The brake shoe assemblies will remain with
the brake caliper. (5) When the caliper is removed from the vehicle
to service the brake shoes. SUPPORT CALIPER
FIRMLY TO PREVENT WEIGHT OF CALIPER
FROM DAMAGING THE FLEXIBLE HOSE. (See
Fig. 3). (6) Remove the outboard brake shoe by prying be-
tween the top of the outboard shoe and the top of the
caliper assembly as shown in (Fig. 4). (7) Remove the inboard brake shoe from the cali-
per, by pulling the inboard shoe assembly away from
the piston (Fig. 5).
Fig. 1 Non-Family Disc Brake Assembly
Fig. 2 Removing Caliper and Brake Shoes as an Assembly
5 - 38 BRAKES Ä

CLEANING AND INSPECTION
Check for piston seal leaks (brake fluid in and
around boot area and inboard lining) and for any
ruptures of the piston dust boot. If boot is damaged,
or fluid leak is visible, disassemble caliper assembly
and install a new seal and boot,(and piston if scored).
Refer to procedures titled Disc Brake Caliper Disas-
sembly. Check the caliper dust boot and caliper pin bush-
ings to determine if they are in good condition. Re-
place if they are damaged, dry, or found to be brittle.
Refer to Cleaning And Inspection Of Brake Caliper.
BRAKE SHOES INSTALL
(1) Thoroughly clean and lubricate both adapter
ways on the steering knuckle, with a liberal amount
of Mopar Multi-purpose Lubricant, or equivalent. (2) The inboard brake shoes are common. The out-
board brake shoes are marked with an (LH) or (RH)
to denote which side of the vehicle to be installed on
(Fig. 6).
(3) Remove protective paper from the noise sup-
pression gasket and position the properly marked
outboard brake shoe assembly onto the caliper (Fig.
7). (4) Install new inboard brake shoe assembly in cal-
Fig. 3 Storing Caliper
Fig. 4 Prying Outboard Shoe Assembly Away from Caliper
Fig. 5 Removing or Installing Inboard ShoeAssembly
Fig. 6 Brake Shoe Identification
Ä BRAKES 5 - 39

iper, by installing retaining clip into the bore of the
piston (Fig. 5).
CAUTION: Use care when installing the caliper as-
sembly onto the steering knuckle, so the seal on the
sealed for life bushings does not get damaged.
(5) Carefully lower caliper over braking disc and
guide holddown spring under machined abutment on
knuckle assembly (Fig. 8).
(6) Install caliper guide pin bolts and tighten to
24-34 N Im (18-25 ft. lbs.) torque. When installing guide pin bolts, use extreme caution not to cross
thread the guide pin bolts.
(7) Install wheel and tire assembly. Tighten stud
nuts in proper sequence until all nuts are torqued to
half specification. This is important. Then repeat
sequence to full specification. (8) Remove jackstands or lower hoist. Before mov-
ing vehicle be sure it has a firm pedal, pump
pedal several times. (9) Road test vehicle and make several stops to
wear off any foreign material on the brakes and
to seat the linings.
DISC BRAKE CALIPER DISASSEMBLY
CLEANING AND INSPECTION
Check for piston fluid seal leaks (brake fluid in and
around boot area and inboard lining) and for any
ruptures of piston dust boot. If boot is damaged, or fluid
leak is visible, disassemble caliper assembly and in-
stall a new seal and boot,(and piston if scored). Refer to
procedures titled Disc Brake Caliper Disassembly. Check the caliper dust boot and caliper pin bushings
to determine if they are in good condition. Replace if
they are damaged, dry, or found to be brittle. Refer to
Cleaning And Inspection Of Brake Caliper. (1) Remove caliper from braking disc (See Brake
Shoe Removal). Hang assembly on a wire hook away
from braking disc, so hydraulic fluid cannot get on
braking disc (See Fig. 3 in Brake Shoe Removal). Place
a small piece of wood between the piston and caliper
fingers. (2) Carefully depress brake pedal to hydraulically
push piston out of bore. (Brake pedal will fall away
when piston has passed bore opening.) Then prop up
the brake pedal to any position below the first inch of
pedal travel, this will prevent loss of brake fluid from
the master cylinder. (3) If both front caliper pistons are to be removed,
disconnect flexible brake line at frame bracket after
removing piston. Plug brake tube and remove piston
from opposite caliper. Using the same process as above
for the first piston removal.
WARNING: UNDER NO CONDITION SHOULD AIR
PRESSURE BE USED TO REMOVE PISTON FROM
CALIPER BORE. PERSONAL INJURY COULD RE-
SULT FROM SUCH A PRACTICE.
(4) Disconnect brake flexible hose from the caliper.
To disassemble, mount caliper assembly in a vise
equipped with protective jaws.
CAUTION: Excessive vise pressure will cause bore
distortion and binding of piston.
Fig. 7 Installing Outboard Shoe Assembly onto Cali- per
Fig. 8 Guiding Holddown Spring Under MachinedAbutment
5 - 40 BRAKES Ä

(5) Clamp caliper in vise (with protective caps on
vise jaws). (6) Remove dust boot from the brake caliper and
discard (Fig. 1).
(7) Using a plastic trim stick, work piston seal out of
its groove in caliper piston bore (Fig. 2). Discard old
seal. Do not use a screwdriver or other metal tool
for this operation, because of the possibility of
scratching piston bore or burring edges of seal
groove. The double pin caliper uses a sealed for life bushing
and sleeve assembly. If required this assembly can be
serviced using the following procedure. (1) Push out and then pull the inner sleeve from
inside of the bushing using your fingers as shown in
(Fig. 3)
(2) Using your fingers collapse one side of the bush-
ing. Then pull on the opposite side to remove the
bushing from the brake caliper assembly (Fig. 4).
CLEANING AND INSPECTION OF BRAKE CALIPER
Clean all parts using alcohol or a suitable solvent
and wipe dry using only a lint free cloth, no lint
residue can remain in caliper bore. Clean out all drilled
passages and bores. (Whenever a caliper has been
disassembled, a new boot and seal must be in-
stalled at assembly). Inspect the piston bore for scoring or pitting. Bores
that show light scratches or corrosion, can usually be
cleared of the light scratches or corrosion using crocus
cloth. Bores that have deep scratches or scoring should be
honed. Use Caliper Hone, Special Tool C-4095, or
equivalent providing the diameter of the bore is not
increased more than 0.0254 mm (0.001 inch) (Fig. 5). If the bore does not clean up within this specification,
a new caliper housing should be installed. Install a new
piston if the old one is pitted or scored. When using Caliper Honing Tool, Special Tool
C-4095, coat the stones and bore with brake fluid.
After honing the bore, carefully clean the seal
and boot grooves with a stiff non-metallic rotary
brush.
Fig. 1 Removing Piston Dust Boot
Fig. 2 Removing Piston Seal
Fig. 3 Removing Inner Sleeve
Ä BRAKES 5 - 41

Use extreme care in cleaning the caliper after
honing. Remove all dirt and grit by flushing the
caliper with brake fluid; wipe dry with a clean,
lint free cloth and then clean a second time.
ASSEMBLING DISC BRAKE CALIPER
Clamp caliper in vise (with protective caps on vise
jaws).
CAUTION: Excessive vise pressure will cause bore
distortion and binding of piston. Dip new piston seal in clean brake fluid and install
in the groove of the caliper bore. Seal should be po-
sitioned at one area in groove and gently worked
around the groove (Fig. 1), using only your fingers
until properly seated. NEVER USE AN OLD PISTON SEAL. (Be sure
that fingers are clean and seal is not twisted or
rolled) (Fig. 1).
Coat new piston boot with clean brake fluid leav-
ing a generous amount inside boot. Position dust boot over piston after coating with
brake fluid. Install piston into caliper bore pushing it past the
piston seal until it bottoms in the caliper bore (Fig.
2).
CAUTION: Force must be applied to the piston uni-
formly to avoid cocking and binding of the piston in
the bore of the caliper.
Fig. 1 Installing New Piston Seal
Fig. 2 Pushing Piston into Bore
Fig. 4 Removing Bushings From Caliper
Fig. 5 Honing Piston Bore
5 - 42 BRAKES Ä

Position dust boot in counterbore of the caliper piston
bore. Using a hammer and Installer Piston Caliper Boot,
Special Tool C-4689 and Handle, Special Tool C-4171,
drive boot into counterbore of the caliper (Fig. 3).
Use the following steps, to install the Guide Pin
Sleeve Bushings into the caliper assembly. (1) Fold the bushing in half lengthwise at the solid
middle section of the bushing (Fig. 4).
(2) Using your fingers insert the folded bushing into
the caliper assembly (Fig. 5). Do not use a sharp
object to perform this step do to possible damage
to the bushing. (3) Unfold the bushing using your fingers or a
wooden dowel until the bushing is fully seated into the caliper assembly. Flanges should be seated
evenly on both sides of the bushing hole in the cali-
per assembly (Fig. 6).
Install the Guide Pin Sleeve into the guide bushing
using the following procedure. (1) Install the sleeve into one end of the bushing
until the seal area of the bushing is past the seal
groove in the sleeve (Fig. 7). (2) Holding the convoluted end of the bushing with
one hand. Push the sleeve through the bushing (Fig.
Fig. 5 Installing Caliper Guide Pin Sleeve Bushings
Fig. 6 Bushing Correctly Installed In Caliper
Fig. 3 Installing Dust Boot in Caliper Counterbore
Fig. 4 Folded Caliper Guide Pin Bushing
Ä BRAKES 5 - 43

7) until the one end of the bushing is fully seated
into the seal groove on the one end of the sleeve. (3) Holding the sleeve in place work the other end
of the bushing over the end of the sleeve and into the
seal grove (Fig. 8). Be sure the other end of the bush-
ing did not come out of the seal grove in the sleeve. (4) When the sleeve is seated properly into the
bushing. The sealed for life bushing can be held be-
tween your fingers and easily slid back and forth
without the bushing seal unseating from the sleeve. Before installing caliper assembly on vehicle, inspect
braking disc. If any conditions as described in Check-
ing Braking Disc for Runout and Thickness are present
the braking disc, must be replaced or refaced. If the
braking disc does not require any servicing, install
caliper assembly. Install brake hose onto caliper using banjo bolt.
Torque the brake hose to caliper assembly banjo bolt to
33 N Im (24 ft. lbs.). New seal washers MUST al-
ways be used when installing brake hose to cali-
per. Bleed the brake system (see Bleeding Brake System).
Fig. 7 Installing Caliper SleevesFig. 8 Installed Caliper Bushing Sleeve
5 - 44 BRAKES Ä

REAR DISC BRAKES INDEX
page page
Assembling Rear Disc Brake Caliper .......... 49
Brake Shoe Removal ..................... 46
Cleaning and Inspection ................... 49
Disassembling Rear Caliper Assembly ......... 48 General Information
....................... 45
Lining Wear ............................. 45
Service Precautions ....................... 46
GENERAL INFORMATION
The rear disc brakes are similar to front disc
brakes, however, there are several distinctive fea-
tures that require different service procedures. This
single piston, floating caliper rear disc brake assem-
bly includes a hub assembly, adapter, braking disc
(rotor), caliper, shoes and linings. The parking brake
system on all vehicles equipped with rear disc
brakes. Consists of a small duo-servo drum brake
mounted to the caliper adapter. The drum brake
shoes expand out against a braking surface (hat sec-
tion) on the inside area of the braking disk (rotor). The AC and AY body vehicles are equipped with a
caliper assembly that has a 36 mm (1.42 inch) piston,
and utilizes a 14 inch solid braking disc (rotor). The AA body vehicle are equipped with a caliper
assembly that uses a 34 mm (1.34 inch) piston. The
AA body uses the same 14 inch solid braking disc
(rotor) as on the AC and AY applications. Also avail-
able on the AA body is a caliper assembly with a 36
mm (1.42 inch) piston, with a 15 inch vented braking
disc (rotor). The AG AJ and AP body vehicles are also equipped
with different size caliper pistons depending on the size and type of braking disk used on the vehicle.
The 14 9solid braking disk (rotor) applications use a
34 mm (1.34 inch) piston, and the 15 9vented braking
disk (rotor) applications use a 36 mm (1.42 inch) pis-
ton. The caliper assembly on all applications float on
rubber bushings using internal metal sleeves which
are attached to the adapter using threaded guide pin
bolts. The adapter is mounted to the rear axle of the ve-
hicle and is used to mount the brake shoes and actu-
ating cables for the parking brake system. The
adapter also mounts the rear caliper assembly to the
vehicle. The adapter has two machined abutments
which are used to position and align the caliper and
brake shoes for movement for and aft (Fig. 1)
LINING WEAR
To check the amount of lining wear, remove the
wheel and tire assemblies. If a visual inspection does
not adequately determine the condition of the lining,
Fig. 1 Rear Disc Brake Assembly
Ä BRAKES 5 - 45